Automatic transmissions for vehicles are in common use, for they are particularly conducive to vehicle efficiency and operator comfort. However, the operational efficiency of an automatic transmission is, in large part, dependent upon the presence of a proper volume of transmission fluid or oil within the transmission itself. Not only is the proper operation of the transmission dependent upon the presence of an appropriate volume of transmission oil, but the same also assures that transmission wear is minimized, prolonging the useful life of the system.
Presently, the fluid level within an automatic transmission is typically monitored through the use of a dipstick. However, for correct fluid level measurement, the dipstick must be properly calibrated for each installation, and the measurements must be taken under optimum or ideal operating conditions. Included among these conditions are an assurance that the transmission oil is at a normal operating temperature, the engine speed or input speed to the transmission is at a set level, and oil drain back or settling time requirements for the transmission have been satisfied. Of course, operator capabilities also impact the accuracy of the reading taken with the dipstick, since any such measurement requires that the operator correctly observe and interpret the difference between the oil line and the full/add lines upon the dipstick. Quite frequently, the requirements for ideal operating conditions and operator capability are not met when the measurement is taken and acted upon. The resultant incorrect automatic transmission fluid level results in poor shift quality, inefficient operation, operator discomfort, and reduced transmission life.
There is a need in the art for an apparatus and technique for fluid level determination in automatic transmissions which automatically accounts and adjusts for less-than-ideal checking conditions, and removes subjective interpretation of measurements in determining the proper deviation of the fluid level in automatic transmissions from a standard acceptable level.